Golf putter

ABSTRACT

This invention relates to a putter, comprising a shaft ( 7 ), a putter head ( 1 ) with a hitting face ( 3 ) and means for attaching the putter head ( 1 ) to the shaft ( 7 ), said shaft ( 7 ) having an imaginary center line ( 8 ) positioned substantially coaxial within said shaft, said putter head ( 1 ) having a center of gravity (x), wherein that the shaft ( 7 ) and the head ( 1 ) are attached to each other in such a manner that a the point of intersecting of said center line ( 8 ) and a normal extending inwardly of said hitting faces ( 3 ) is positioned at a longer distance from said hitting face ( 3 ) than the centre of gravity (x), so as to form a minimum distance (L) between said center line ( 8 ) and said centre of gravity (x).

This invention relates to a golf putter and especially a new manner ofattaching the putter head to the shaft.

PRIOR ART AND PROBLEMS

The put requires enormous accuracy. It is evident that the shape anddesign of the putter does have a major influence on the performance whenputting.

Many different designs and shapes have been suggested in order toimprove accuracy. Originally, a putter head had a blade shape with theshaft attached thereto at the heel part, a design which goes back to thenineteenth century. In the meantime many different designs and shapeshave been tried, e.g. a semi-spherical shaped putter head, the use ofbalancing weights, attachment of the shaft at the toe part of the putterhead, attachment of the shaft near the centre of gravity of the shaft,etc. None of these differing designs have revolutionised the golf sport,but the different designs are used in a large variety among the players.

In contrast to other strokes the movement of the putter is relativelyslow. Accordingly the player can be assisted by a sight line on theputter head in order to obtain extra accuracy of the movement whenstriking the golf ball. However, known putters do not provide means fora sight line which comes near the feeling of accuracy as with a cue whenplaying pool.

Furthermore, many putters of today have an attachment of the shaft tothe putter head which is totally balanced when keeping the hitting faceof the putter head upwards. This means that there will be no momentum inthe shaft when moving it in a direction that is perpendicular to thehitting face. Accordingly, the player will not notice any torque of theshaft during the movement of the putter head if the putter head isrotated during the striking movement. Consequently, the player does notsense by means of a force of torque of the shaft if the putter head ismoved out of the extension of the sight line when putting.

Finally, it appears that none of the existing putters does give theplayer a distinct feed back when hitting the golf ball in an exactlyaccurate manner.

From U.S. Pat. No. 4,702,477 there is known a putter which at firstsight might appear to eliminate some of the conventional disadvantagesmentioned above. Accordingly, U.S. Pat. No. 4,702,477 presents a puttercomprising a shaft, a putter head with a hitting face and means forattaching the putter head to the shaft, said shaft having an imaginarycentre line positioned substantially coaxial within said shaft, and,wherein said means comprises an attachment device having at least onerod shaped part having an imaginary centre line, wherein said rod shapedpart is attached to the putter head so as to have said imaginary centreline extending substantially perpendicular in relation to the hittingsurface of the putter head. However, the rod shaped part as shown inU.S. Pat. No. 4,702,477 is merely intended for increasing the golfersperipheral vision in the direction of the desired path of golf balltravel by providing for a location of the golf ball which is closer tothe golfers front foot than is normally the case. Accordingly, the rodshaped part of U.S. Pat. No. 4,702,477 is not intended for providing asight line, but is positioned off-centred in relation to spot forhitting the golf ball. Nor does the attachment according to U.S. Pat.No. 4,702,477 indicate any distinctive torque to the player if theputter head is rotating during the striking movement. Finally, U.S. Pat.No. 4,702,477 does not provide any means for giving the player adistinct feed back when hitting the golf ball in an exactly accuratemanner.

SOLUTION AND ADVANTAGES

It is the object of the invention to provide a putter which eliminatesor at least minimises the disadvantages mentioned above. This isachieved by a putter, comprising a shaft, a putter head with a hittingface and means for attaching the putter head to the shaft, said shafthaving an imaginary centre line positioned substantially coaxiallywithin said shaft, said putter head having a centre of gravity, saidmeans comprising an attachment device having at least one rod shapedpart with an imaginary centre line, said rod shaped part being attachedto the putter head so as to have said centre line extendingsubstantially perpendicular in relation to the hitting surface of theputter head, characterised in that said rod shaped part extends all theway through said putter head to form a part of the hitting surface, andthat said part of the rod which forms a part of the hitting surface ispositioned within the hitting surface in such a manner that the rodshaped part forms an extended sight line for extra accuracy of themovement when hitting a golf ball with the putter head.

The above mentioned design provides a putter which can provide anextended and distinct sight line in order to facilitate a movement alonga straight line of the putter head. The invention will give the player asimilar feeling of accuracy as a pool player since he will actually havethe possibility to see a rod shaped part move along the sight linegiving a feeling of extra accuracy.

Accordingly the invention provides a new kind of a putter having thefollowing advantages:

improved and extended sight line;

favourable feed back when hitting the ball accurately; and

an attachment t hat may eliminate twisting of the shaft and the putterhead during the stroke.

According to further aspects of the invention:

said front part of the rod shaped part is positioned to intersect avertical centre line of the hitting surface, preferably substantiallycentered in relation to said centre line;

said attachment device is L-shaped and comprises a further rod shapedpart, a neck portion, which preferably extends substantially coaxiallywith said centre line of said shaft;

said putter head is arranged with a rearwardly extending protrusion,preferably forming an integral part thereof, for attachment of the shaftthereto;

there is arranged a sight line on top of the putter head, extending atleast a portion between the point of attachment of the shaft and theupper edge of the hitting surface;

said imaginary centre line of the shaft and a normal of the hitting faceforms an angle α which is less than 90° in a plane that is parallel tothe centre line of the shaft and perpendicular to the hitting face;

the angle α is such that the top end of the shaft is positionedsubstantially in the same plane as the hitting face;

the putter head is pivotally adjustably attached to said rod, preferablyby means of a screw which may be tightened in a threaded bore of thehead;

said imaginary centre line of the rod shaped part is positioned within adistance from the lower part of the putter head that is between 15 and25 mm, preferably about 20 mm, and preferably in that the hitting facehas a plane that opens up about 2-5° in relation to a vertical plane;

the shaft and the head are attached to each other in such a manner thata point of intersecting of said centre line and a normal extendinginwardly of said hitting face is positioned at a longer distance fromsaid hitting face than the centre of gravity x, so as to form a minimumdistance L between said centre line and said centre of gravity x;

said minimum distance L exceeds 10 mm and is less than 100 mm,preferably exceeds 20 mm, and more preferred exceeds 30 mm, or even morepreferred exceeds 40 mm;

said rod shaped part has a contrasting colour in relation to theupwardly facing surface (1C) of the rearwardly extending protrusion(1A).

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing objects and advantages of the invention, together withother objects and advantages which may be achieved by using theinvention, will become more apparent upon reading the following detaileddescription of the invention in conjunction with the drawings. In thedrawings:

FIG. 1 is a side view of a putter illustrating the principles of theinvention;

FIG. 2 is a perspective view of a preferred embodiment of the invention;and

FIG. 3 is perspective view of a further embodiment according to theinvention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a golf putter according to the invention, comprising ashaft 7 and a putter head 1 with a hitting surface 3. Between the shaft7 and the putter head 1 there is an L-formed attachment means 2 forattaching said putter head to said shaft

The shaft 7 has an imaginary centre line 8 positioned substantiallycoaxially within said shaft. The shaft has a circular cross-sectionwhich tapers downwards. The L-formed attachment means 2 comprises ahorisontally extending rod shaped part 6A and vertically extending neckportion 6B. The shaft is connected to the upper end 5 of the verticallyextending neck portion 6B, preferably by means of an adhesive. Theputter head 1 is attached to the horisontally extending rod shaped part6A by means of a threaded bore 10 within which a screw 11 is tightenedagainst the rod 6A. The rod shaped part 6A protrudes through the centreof gravity x all the way through said putter head 1, such that the endsurface 6C forming a part of the hitting face 3. The visual part of thehorisontally extending rod shaped part 6A forms an extended sight linefor extra accuracy of the movement when hitting a golf ball with theputter along a straight line. Furthermore, the top of the club head isarranged with a marked sight line (see 1B in FIG. 2), in a traditionalmanner.

The vertically extending neck portion 6B is coaxial with the centre axis8 of the shaft 7. When the horisontally extending rod 6A is positionedexactly horisontally, the hitting face 3 will be positioned slightly outof the vertical plane, so as to form an open angleβ, i.e. a loft ofabout 4° . Also the shaft is inclined with an angle α so that the top ofthe shaft, i.e. the handle, will be positioned in about the same planeas the hitting face 3.

The putter head has a centre of gravity x. The shaft 7 and the head 1are attached to each other in such a manner that the imaginary centreline 8 of the shaft intersects the imaginary centre line 9 of thehorisontally extending rod shaped part 6A at a distance L from saidcentre of gravity x. This distance, L, may vary depending on personaldesires, weight of the putterhead etc, but its length must never exceeda certain limit since according to rules a head may not be deeper thanwider. Normally the distance, L, would not exceed 8 cm, preferably itwould be within the range of 3-7 cm. In the shown figure said distance Lis about 5 cm. According to the design shown in FIG. 1 the imaginaryline 9 of the horisontally extending rod shaped part 6A intersects thecentre of gravity. Modifications are of course possible without loosingthe advantages of the invention, e.g. the imaginary line of thehorisontally extending rod shaped part 6A may be positioned higher up orfurther down but substantially within the same plane as the force vectorof the centre of gravity x when the head is positioned with its bottomportion in a horizontal position, i.e. resting against the ground.Furthermore it may also be positioned slightly out of said plane.Moreover, it is not essential that the rod shaped part 6A is positionedexactly horisontally (as described above), since the player looks at itfrom above.

The distance indicated with z is the distance from the bottom border ofthe hitting face 3 to the point where the centre line 9 of thehorisontally extending rod 6A intersects the hitting surface 3. Thisdistance is about 20 mm.

According to a preferred embodiment the putter head 1 is symmetrical inrelation to a vertical plane which comprises the centre line 3A of thehitting surface 3 and which is arranged perpendicularly in relation tothe hitting surface 3. (See FIGS. 2 and 3). Furthermore the rod shapedpart 6A extends through the centre line 3A (see FIG. 3) of such asymmetrical putter head, in such a manner that it intersects the centreof gravity and such that its front end 6C is positioned at the centre ofsaid line of symmetry.

To get a good hit with the putter giving the ball the right mode ofrotation the point 6C of the hitting surface 3 should strike the golfball slightly below its centre point. The angle β of inclination of theface 3 is also important for the strike and has an influence on therotation mode of the ball.

During use, a putter according to the design of the invention willcreate a torque of the shaft, if the putter is moved out of positionfrom the sight line, since there is a substantial distance between thepoint of attachment of the shaft and the centre of gravity of the putterhead, which creates a momentum, i.e. a force of torque of the shaft ifinaccurately positioned during the stroke.

Moreover, the preferred embodiment for attaching the head to the shaftdoes comprise a rod shaped part of substantial length, which rod shapedpart is positioned substantially perpendicularly in relation to thehitting face of the putter head, so as to form said extended sight line.This special feature of the invention will give the player a similarfeeling of accuracy as a pool (billiard) player since he will actuallyhave the possibility to see a rod shaped part move along the sight linesignalling a feeling of extra accuracy.

Since the horizontal, rod shaped part protrudes through the putter head,its end face is co-planar with the hitting face. The end face of the rodis positioned at the optimal point for hitting the ball. Thanks to thisdesign the player will be able to actually sense, by means of vibrationsin the shaft, when an accurate hit of the ball is performed.

FIG. 2 shows a preferred embodiment of a golf putter according to theinvention. A major difference in relation to FIG. 1 is that the putterhead 1 is arranged with a rearwardly extending protrusion 1A at itslower portion. Also here, the extended sight line is achieved by havingan L-shaped attachment device 2 which comprises one horisontallyextending rod shaped part 6 A, which is attached substantially at thecentre of the rearwardly facing part 1C of the head 1. The other rodshaped part 6B, the neck, does not extend exactly coaxially with saidcentre line 8 of said shaft 7, but forms a minor angle in order toachieve that it can be positioned with its imaginary centre line in thesame plane as the player positions his eyes during the stroke. Theimaginary centre line 9 of the horisontally extending rod shaped part 6Aextends substantially perpendicular in relation to the hitting surface 3of the putter head, to form said extended sight line for extra accuracyof the movement when hitting a golf ball with the putter head movingalong a straight line. As shown, the sight line 1B is prolonged at thetop of the head 1 by a blackened groove. Furthermore, a wide area 1Cbelow the horisontal rod 6A is blackened in order to improve accuracy,which is achieved by the contrast it creates in relation to the metallicsurface of the rod 6A.

In FIG. 3 there is shown a modified embodiment of the invention. Thedesign is basically the same as shown in FIG. 2 except for the rodshaped horizontal part 6A, which forms an integral part of said putterhead 1. Accordingly the head is preferably produced as one single part,e.g. by casting, including the rod shaped horizontal part 6A.Preferably, the rod shaped part 6A is made of a different material thenthe rest of the putter head 1, in order to provide for the feeling ofdistinct feed back as described above. Accordingly, the front end 6C ofsuch a rod shaped part 6A will form a part of the hitting surface 3. Ascan be seen in FIG. 3 the rod 6A is positioned such that its front end6C is centred in relation to a vertical centre line 3A of the hittingsurface 3. FIG. 3 shows the use of an attachment device 2, in the formof a neck portion between the shaft 7 and the head 1, but as is evidentfor the skilled man this attachment may be achieved by attaching theshaft directly to the head 1. Furthermore, FIG. 3 shows that furtheraccuracy may be obtained by prolonging the sight line 1B to also runalong the rod shaped part 6A, which of course also may be utilized inconnection with the other embodiments.

The skilled man realises that the invention is not limited to the aboveshown embodiments, but that it may be varied within the scope of theclaims. For instance instead of having the attachment point of the rod6A near the midpoint of the head so that it is positioned within thesame plane as the vector of the centre of gravity x, it may also bepositioned somewhat off-centred if a player would desire to feel sometorque during the stroke. Furthermore, it is evident that there existmany different obvious alternatives of attaching the shaft to theL-shaped attachment device as is also the case in relation to theattachment of the head. Moreover, it is evident that many othercontrasting colours than metalic/black may be used in order todistinguish the rod from the putter head.

What is claimed is:
 1. Putter, comprising a shaft (7), a putter head (1)with a hitting face (3) and means for attaching the putter head (1) tothe shaft (7), said shaft (7) having an imaginary centre line (8)positioned substantially coaxially within said shaft, said putter head(1) having a centre of gravity (x), said means comprising an attachmentdevice (2) having at least one rod shaped part (6A) with an imaginarycentre line (9), said rod shaped part (6A) being attached to the putterhead so as to have said centre line extending substantiallyperpendicularly in relation to the hitting surface (3) of the putterhead, characterised in that said rod shaped part (6A) extends all theway through said putter head to form a part (6C) of the hitting surface(3), and that said part (6C) of the rod (6A) which forms a part of thehitting surface (3) is positioned within the hitting surface (3) in sucha manner that the rod shaped part (6A) forms an extended sight line forextra accuracy of the movement when hitting a golf ball with the putterhead (3).
 2. Putter according to claim 1, characterised in that saidpart (6C) of the rod shaped part (6A) is positioned to intersect avertical center line (3A) of the hitting surface, substantially centeredin relation to said center line (3A).
 3. Putter according to claim 1,characterised in that said attachment device (2) is L-shaped and that itcomprises a further rod shaped part, a neck portion (6B), which extendssubstantially coaxially with said centre line (8) of said shaft (7). 4.Putter according to claim 1, characterised in that said putter head (1)is arranged with a rearwardly extending protrusion (1A), forming anintegral part thereof, for attachment of the shaft (7) thereto. 5.Putter according to claim 4, characterised in that said rod shaped part(6A) has a contrasting colour in relation to the upwardly facing surface(1C) of the rearwardly extending protrusion (1A).
 6. Putter according toclaim 1, characterised in that there is arranged a sight line on top ofthe putter head (1, 1A) extending at least a portion between the pointof attachment of the shaft (7) and the upper edge of the hitting surface(3).
 7. Putter according to claim 1, characterised in that saidimaginary centre line (8) of the shaft (7) and a normal of the hittingface (3) forms an angle (α) which is less than 90° in a plane that isparallel to the centre line of the shaft (7) and perpendicular to thehitting face (3).
 8. Putter according to claim 7, characterised in thatthe angle (α) is such that the top end of the shaft is positionedsubstantially in the same plane as the hitting face (3).
 9. Putteraccording to claim 1, characterised in that the putter head (1) ispivotally adjustably attached to said rod by means of a screw (11) whichis tightened in a threaded bore (10) of the head (1).
 10. Putteraccording to claim 1 characterised in that said imaginary centre line ofthe rod shaped part (6A) is positioned within a distance from thelowermost part of the putter head (1) that is between 15 and 25 mm, andin that the hitting face (3) has a plane that opens up about 2-5° (β) inrelation to a vertical plane.
 11. Putter according to claim 1,characterised in that the shaft (7) and the head (1) are attached toeach other in such a manner that a the point of intersecting of saidcentre line (8) and a normal extending inwardly of said hitting faces(3) is positioned at a longer distance from said hitting face (3) thanthe centre of gravity (x), so as to form a minimum distance (L) betweensaid centre line (8) and said centre of gravity (x).
 12. Putteraccording to claim 11, characterised in that said minimum distance (L)exceeds 10 mm and is less than 100 mm.
 13. Putter, comprising a shaft 8,a putter head 1 with a hitting face 3 and means for attaching the putterheard 1 to the shaft 7, said shaft 7 having an imaginary center line 8positioned substantially coaxially within said shaft, said putter head 1having a center of gravity (x) said means comprising an attachmentdevice 2 having at least one rod-shaped part 6A with an imaginary centerline 9, said rod-shaped part 6A being attached to the putter head so asto have said center line extending substantially perpendicularly inrelation to the hitting surface 3 of the putter head, characterized inthat said rod-shaped part 6A extends in such a manner than therod-shaped part 6A forms an extended sight line for extra accuracy ofthe movement when hitting a golf ball with the putter head 3, that saidputter head 1 is arranged with a rearwardly extending protrusion 1A andthat said rod-shaped part 6A has a contrasting color in relation to theupwardly facing surface 1C of the rearwardly extending protrusion 1A,and characterized in that said putter head 1 is arranged with arearwardly extending protrusion 1A, preferably forming an integral partthereof, for attachment of the shaft 7 thereto.